per·i·stal·sis 
(p
ĕr
′ĭ-stôl
s
ĭs, -st
ăl
-)
n. pl. per·i·stal·ses (-s
ēz)
The wavelike muscular contractions of the digestive tract or other tubular structures by which contents are forced onward toward the opening.
[New Latin, from Greek peristaltikos, peristaltic, from peristellein, to wrap around : peri-, peri- + stellein, to place; see stel- in the Appendix of Indo-European roots.]
per′i·staltic (-stôltĭk, -stăl-) adj.
per′i·stalti·cal·ly adv.